Changing backgroun for special customers

I'd like to know if it is possible to have something change on the screen for my service reps when someone has a certain label on their account from a drop down.

For example, if I create a drop dox called "Client" and we want to flag people's accounts, such as a "gold customer" or some other flag, I would like to make the background change so that when one of our customer srevice reps brings up the account maybe a large star/flag image appears, or perhaps the background changes, or something blinks on the screen.